The following U.S. patents and U.K. published application are incorporated herein by reference in entirety.
U.S. Pat. No. 4,743,154 discloses a pallet repair and inspection system including pallet destacking apparatus for automatically dispensing pallets from a stack of vertical pallets one at a time and discharging the pallets onto an inspection table. The destacking apparatus includes a vertically reciprocating table onto which the stack of pallets is driven, and horizontally reciprocating forks which are operated to suspend all but the lowermost pallet as the table is successively lowered and raised between a pallet discharge height and a pallet pick-up height, to discharge the pallets into the inspection table one at a time. The top of the inspection table is foldable to define a cradle for one end of the pallet, orienting the pallet generally vertically, and allowing inspection of its top and bottom surfaces.
U.S. Pat. No. 5,630,695 discloses a sorting machine having a lifting and rotating apparatus which includes a rotatable platform upon which a stack of pallets can rest so as to be supported from underneath. A scissor lift is provided for raising and lowering the stack so that the uppermost pallet is moved firstly to an inspection level where it is rotated with the rotatable platform for exposing its top and sides to an operator and then to a transfer level. The machine also has a support device having tynes which move into an extended position to support and maintain the pallet at the transfer level when the scissor lift is lowered to thereby expose the bottom of the pallet to the operator. A transfer carriage engages opposite sides of the pallet and supports the pallet from underneath. The pallet is then transported by the transfer carriage to one of a plurality of outfeed stations after the support device is moved into its retracted position.
U.S. Pat. No. 6,892,592 discloses an automated system for checking the structural integrity of pallets which, after suitable programming, checking operations and through special pliers can carry out further handling operations on the pallets between any combination of fixed surfaces. This system stacks pallets performing the typical functions of traditional stackers and de-stackers, and eliminating the needs of bulky transport paths and complex connecting deviations.
U.S. Pat. No. 7,340,971 discloses a system and method for inspecting pallets that verifies a pallet meets dimensional and structural integrity requirements for transporting a load. The method and automated system further verifies that a pallet is within tolerances for dimensions, the load-bearing surface of the pallet is free from large voids or damage, and that the pallet is able to withstand stress associated with a load and support. Pallets are rejected when one or more defects are found in the pallet as determined by signals from various inspection stations generated in response to performance of structural tests on the pallet.
U.S. Pat. No. 7,765,668 discloses an automatic pallet inspection cell comprising one or two multi axis robot arms which terminate in either internal or external pallet grippers. The robots are used to transport a gripped pallet through an automated inspection station which compiles a three dimensional data map of a pallet surface. A processor interprets the map and produces a recipe for the robot or robots. One or more stations conduct pallet repair operations that are specified by the map recipe. A method for levelling a pallet prior to board removal by a band saw is also disclosed, characterized by rolling the pallet relative to a blade of the band saw to a first and a second roll angle, and positioning the pallet at a position which is an average of the first and second roll angles.
U.S. Pat. No. 7,958,624 discloses an automated pallet inspection and repair apparatus which includes an inspection station and a repair station. The inspection station includes a laser that illuminates a pallet, a camera that collects the reflected light and a computer system. The computer system analyzes the output of the camera and acquires the pallet's geometry and topography. The design of the pallet is determined by the computer software. A decision to repair the pallet is made by comparing the acquired pallet data against the design criteria. If the pallet needs repair, a recipe of repair steps is constructed by inspecting each of the pallet's elements. The recipe is transmitted to the automated repair station.
U.K. Published Patent Application No. 2056681 discloses a pallet testing and sorting machine characterized by a gripper mechanism which by means of clamping or gripper jaws is adapted to lift and convey the top pallet from a stack thereof for testing. The machine includes a test mechanism to which the pallets are adapted to be fed individually by the gripper mechanism, and which comprises sensing strips adapted to be moved laterally against the pallet for testing the length and breadth dimensions. A plurality of pressers act on the loading surface to test the height dimension by subjecting a number of points to loading. An ejection mechanism is supplied for rejecting a pallet found to be defective by a test mechanism, and a stacking mechanism is provided for the pallets found to be non-defective by the test mechanism. The stacking mechanism is adapted to push each pallet beneath the raised stack.